The invention concerns a label transfer system for a labeling station, especially a gripper cylinder, with a carousel on which there is disposed eccentrically at least one label affixing member, and especially a pair of label affixing members with associated gripper assemblies, which is moved on an arcuate path past a revolving carrier bearing a corresponding number of gluing segments, and on which the gluing segment or segments, which are disposed eccentrically on the carrier and rotate about their own axes, roll as they transfer the label or pair of labels, and which affixes the transferred label or pair of labels as it moves past a revolving object which is advanced on a transport path, especially one which is to be labeled on various diameters.
In labeling machines the affixing of labels to the objects which are to bear them presents certain difficulties inasmuch as the requirement of synchronism between the revolving object and the affixing means during the label affixing operation is not easy to achieve. This is especially true if objects of varying diameter, such as bottles, for example, are to be provided with a breast label and a back label. In the case of a labeling station having gluing segments mounted eccentrically on the carrier and revolving about their own axes, it is necessary, for the achievement of a reliable picking up of the glue-coated labels by the gripper members and the affixing members, that the said gripper members and affixing members move on the same arcuate path in the label transfer area, both for the back label and for the breast label, because the glue segments are able to perform a rolling movement only along this path. The required rolling operation makes it necessary, furthermore, that the speed of movement of the gripper means and affixing members be matched to that of the gluing segments. This speed and the arcuate path, however, are not capable of assuring a rolling movement in the affixing of the labels to begin with. The speed and the arcuate path are optimum with regard to the required rolling movement only for a single diameter of an object rotating at a certain rotatory speed. It is therefore necessary to adapt the speed of the gripper means and affixing members in the area where the labels are transferred to the object to the circumferential speed of the object. This adaptation is especially necessary when one and the same object is to be labeled simultaneously in the area of two different diameters. Whereas it is possible to adapt the circumferential speed and the arcuate path of the gripper means and affixing members to the circumferential speed of the bottle and to the transport path within this area for the label that is intended for the first diameter, without thereby impairing the rolling action of the gluing segments, such adaptation is not possible for labeling the breast of the bottle or the neck of the bottle. In order to label the neck of the bottle, the affixing member would have to be displaced further out in the radial direction. If the rotatory speed is the same for the affixing member which applies the belly label as it is for the affixing member which applies the breast label, this results in a higher circumferential speed; the circumferential speed of the breast or neck of the bottle, on the other hand, is lower than that of the belly of the bottle. Therefore, a still greater relative movement would take place between the affixing member and the breast or the neck of the bottle.
In the awareness of these difficulties, in a known machine the pad for affixing the neck label to the neck of the bottle affixes the label with a slapping movement, so that no rolling movement can occur. This slapping movement, however, not only is expensive to produce, but also it does not guarantee the reliable affixing of the label.